Recently, a technique for connecting a computer with plural storage apparatuses through communication lines (a storage area network (SAN)) to centrally manage the storage apparatuses connected to the SAN has been proposed.
One method of managing plural storage apparatuses connected to a SAN is a technique in which storage areas of the plural storage apparatuses connected to the SAN is collectively managed as a storage pool to make effective use of the storage capacities or extents of the storage apparatuses connected to the SAN.
As the amount of data increases with the growth of computerization, a company often needs to replace an already-possessed storage apparatus with a new storage apparatus of larger memory sizes. In this case, only data in a previously-used storage apparatus is erased, and the storage apparatus is often reused without being scrapped.
On the other hand, a computer writes management information necessary for using a storage apparatus into the storage apparatus.
For example, a PC/AT compatible computer (“PC/AT” is a trademark of IBM Ltd., and is called “PC” below) divides a storage area of a storage apparatus into plural partitions so that each of the divided areas is used independently. In this case, management information (MBR: Master Boot Record) related to this division is written into the first sector of a storage medium such as a hard disk loaded in the storage apparatus.
Even in an environment in which a storage apparatus is centrally managed in a storage pool, management information used by a computer such as MBR is written into the storage apparatus. If such a storage apparatus in which the management information is written is allocated to another computer connected to the SAN, the other computer cannot use the storage apparatus normally or cannot recognize the storage apparatus correctly. In this case, a system manager needs to take on the task of solving this problem such as erasure of the management information in addition to the management work in the storage pool.
Further, when a storage apparatus is shared in the storage pool among plural computers and a system manager forgets to erase important data written while one computer is using it, another computer to which the storage apparatus is allocated next may read the important data which is forgot to be erased.